Device for conveying high-volatile fuel



Jan/5, 1937. T. v. DILLSTRUM 2,065,673

' DEVICE FOR CONVEYING HIGH VOLATILE FUEL I Filed Oct. 22, 1932 2 Sheets-Sheet l INVENTOR 1/3 ATTORNEY Jan. 5, 1937. T. v. DILLSTRUM DEVICE FOR CQNVEY'ING,HIGH VOLATIIQE FUEL Filed Oct. 22, 1932 2 Sheets-Sheet 2 INVENTOR M 7 ///5 ATTORNEY Patented Jan. 5, 1937 YPA'FENT' OFFICE 2,066,673 DEVICE FOR CONVEYIG HIGH-YOLATILE Torbjiirn Viktor Dillstriim, Stockholm, Sweden, assignor to Hcsselman Motor Corporation, Ltd.,

London,

England, Britain a corporation of Great Application October 22, 1932, Serial No. 639,062 In Germany October 29, 1931 6 Claims.

This invention relates toa conveying device for relatively high-volatile fuel of the kind having parts which are lubricated with lubricating oil. The attempts hitherto made to utilize, for such fuels, the pumps employed, especially in internal-combustion engines, for the injection of relatively non volatile fuels, have mostly failed because no'effective means was available for preventing thefuel from passing from the pump 10 into the parts lubricated with lubricating means,

so as to prevent for instance dilution of the lubrlcating oil and consequent damage to said parts. It is the principal object of the present inven- 5 tion to obviate the foregoing drawback in a simple manner. To this end, according to the invention, at those places where the fuel (leakage in particular) could find its way out'of the pump to the parts lubricated with lubricating means,

the escaping fuel is vaporized by suitable means,

' such as a current of air.

In order more clearly to understand the invention, reference is made to the accompanying drawings which illustrate, partly in section, em-

bodiments of conveying devices in accordance therewith.

Fig. 1 is a side elevation of an internal combustion engine with a conveying device embodying the invention and Fig. 2 is a central longitudinal section on an enlarged scale of a one-cylinder pump device, similar to the multicylinder pump shown in Fig. l.

In said drawings A denotes an internal combustion engine with induction pipe B and throttle valve C. From the crank shaft D of the engine a pump 1 and a fan E are driven by suitable means as the gear F and the belt G.

Turning now to Fig. 2 reference numeral [1 denotes the casing of a fuel pump composed of the piston 2, pump barrel 3, suction pipe 4, inlet valve 5, delivery valve 6 and the delivery pipe I leading to an injection nozzle.

The piston is actuated from the camshaft B by way of the roller tappet 9 during the delivery 5 stroke, and by the recoil spring l'lduring' the suction stroke.

, The pump and actuating gear are mounted in a casing III enclosing a chamber H in which the tappet drive and the piston meet. On the one side, said chamber I l is provided with an inlet {2, and on the other with an outlet -l3, for an air current that is passed through the chamber H.

In the embodiment shown, the air current forms the means for vaporizing the fuel leaking from the fuel pump, and this air current can be generated in various ways. Thus a pipe M attached to the outlet I3, may lead to the induction pipe 13 of the internal combustion engine shown in Fig. 1, into the combustion chamber of which v gasoline is injected by the pump "I. In such case, a powerful current of air is drawn through the chamber l l during the suction stroke. The ventilation may also be provided by a fan E which, when the pump is employed on a vehicle, may be the fan of the water-cooling system, as shown.

In order to increase the protection of the lubricated parts of the pump gear, a protective cap i5 is arranged around the tappet push rod in the chamber II I, which cap may also be provided with special means for wiping fuel off the push rod.

In this embodiment, the cap it is mounted in a-- fixed position in the chamber H, for example by bolting it on to the throat I 3 of the casing Illl, so that the cap can serve, at the same time, as a support for the recoil spring it of the tappet.

It will be apparent that many changes and modifications may be made within the scope of the present invention. Thus pipe it may not lead to the induction pipe but to another point if so wanted.

What I claim is:

1. In combination, an internal combustion engine, means for supplying high-volatile fuel to the engine comprising fuel injecting means and a pump for forcing fuel to said injecting means, said pump comprising a casing providing a barrel and a chamber below said barrel, a pump plunger in said barrel, a. spring for actuating said plunger on its suction stroke, lubricated tappet means mounted in said casing below said chamber and reciprocable to actuate said plunger on its discharge stroke, and means for preventing flow to the lubricated portion of said tappet means of fuel leaking past said plunger comprising wiping means engaging said tappet and means for causing flow of air through said chamber between said wiping means and said plunger whereby to vaporize fuel leaking past said plunger. I 2. In an internal combustion engine adapted to be operated with high-volatile fuel, fuel in- 2 intake manifold, means for supplying high-volatile fuel to the engine comprising a pump having a plunger, 9. fuel chamber at one end of the plunger and lubricated means at the other end of said plunger for actuating the plunger, a fan driven by said engine, means for directing a current of air produced by said fan past said other end of said plunger to vaporize fuel leaking past the plunger, and a conduit for conducting the air pump'unit having a portion including a plurality of pump plungers for forcing fuel separately to separate injectors, a base portion housing lubricated shaft and tappet mechanism for operating said plungers, and an intermediate portion providing a space between the first mentioned portion and said base portion in which said plungers and tappets contact, said intermediate portion having an inlet opening and an outlet opening, and meansfo'r causing a current of air to flow from the inlet opening through said space to the outlet opening over said tappets and plungers to vaporize and conduct in vapor form from said space fuel leaking past said plungers.

5. In combination with an internal combustion engine of the injection type, means for injecting high-volatile liquid fuel thereto, including an injector, a pump having a plunger, engine actuated mechanism for moving said plunger on its discharge stroke to force fuel to said inJector, said mechanism including lubricated bearing parts disposed immediately below said plunger in a position to be contacted by liquid fuel leaking past said plunger and means for causing flow of air through the space between said plunger andsaid lubricated bearing parts to remove from the plunger in vapor form fuel leaking past said plunger before such leaking fuel can reach any of said lubricated bearing parts.

6. In combination with an internal combustion engine of the injection type, means for injecting high-volatile liquid fuel thereto, including an inl jector, a pump having a plunger, engine actuated mechanism for moving said plunger on its discharge stroke to force fuel to said injector, said mechanism including lubricated bearing parts disposed immediately below said plunger in a position to be contacted by liquid fuel leaking past said plunger and conduit means connecting the space between said plunger and said lubricated bearing parts with the air intake of the engine for causing flow of air through said space to vaporize and remove from the pump in vapor form fuel leaking past said plunger before such leaking fuel can reach any of said lubricated bearing parts.

TORBJORN VIKTOR DILLSTRbM. 

